This disclosure relates to X-ray imaging, and more particularly to the dynamic low-dose imaging of an object or subject with a moving detector, as well as to the dynamic low-dose tomosynthesis and limited-angle tomographic imaging of a subject with a moving detector and a moving X-ray source. Exemplary applications are in the sub-fields of fluoroscopy, radiography, and cardiology. Other applications are in the fields of non-destructive testing, homeland security and animal imaging.
X-ray fluoroscopy was developed shortly after Roentgen discovered X-rays, using a fluorescent screen. Fluoroscopy developed rapidly to provide an essential investigative and interventional tool. Major advancements occurred in the 1940s-1950s with the development of the image intensifier, and in the mid 1970s when investigators began applying digital technology to fluoroscopic imaging. According to a publication of the National Cancer Institute (NCI) and The Society of Interventional Radiology, “Interventional fluoroscopy represents a tremendous advantage over invasive surgical procedures, because it requires only a very small incision, substantially reduces the risk of infection and allows for shorter recovery time compared to surgical procedures” (NCI. Interventional Fluoroscopy, Reducing Radiation Risks for Patients and Staff. NIH Publication No. 05-5286, 2005) As an example of this advantage, the number of cardiac procedures being performed through Percutaneous Transluminal Coronary Angioplasty (PTCA) continues to increase rapidly, see FIG. 17. About 657,000 such procedures were performed in 2002 in the USA; this procedure is now recommended whenever possible as first-line treatment for ST-Elevation Myocardial Infarction (STEMI) heart attacks.
The total number of minimally invasive image guided interventions (IGI) procedures, (ranging from cardiac electrophysiology to neurology and including treatment of liver cancers, vertebroplasty, abdominal aortic aneurysm treatments and urinary tract procedures) is expected to keep increasing, due to the development of new devices and procedures and the aging of the population. Fluoroscopy is commonly used for guidance and monitoring of IGI procedures. As applied to electrophysiology (EP) diagnosis and treatment, the number of hospitalizations for atrial fibrillation (either as primary or secondary diagnosis, with a predominant increase in the later) have increased 450% from 1983 to 2003
In addition to interventional procedures, Fluoroscopy is also commonly used for many diagnostic procedures such as diagnostic coronary angiography and endoscopic retrograde choleangiography (ERCP).
According to reports received by the FDA of skin injury from fluoroscopy, the two procedures with the largest number of injury reports are RF cardiac catheter ablation and coronary angioplasty. The treatment of coronary disease is also a field where reduced radiation exposure would be advantageous. Currently, treating Chronic Total Occlusions (CTOs) present significant challenges as visualization of occlusions, even with retrograde contrast injection, is difficult using current fluoroscopy systems due to the lack of occluded structure contrast in the images.